<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>外部样式</title>
    <!-- 通过link标签的href属性导入外部css文件 -->
    <link rel="stylesheet" href="css/base1.css">
</head>
<body>
    <div>div1</div>
    <span>span1</span>
    <p>段落1</p>
</body>
</html>